Patent attributes
A linear motor not requiring a yoke structure is provided. A first unit forming a stator is constructed of two permanent magnet rods. The permanent magnet rods each have a magnetically permeable shaft and a permanent magnet row having a plurality of permanent magnets so arranged that opposite polarities of their magnetic poles alternately appear. The permanent magnet row of the permanent magnet rod is arranged with a positional difference of 180° in an electrical angle from the permanent magnet row of the permanent magnet rod. The second unit that constitutes a moving member includes unit cores and winding sets arranged alternately in an axial direction of the shaft. The winding set includes two excitation windings through each of which the permanent magnet rod loosely extends. One excitation winding of the winding set is excited with a phase difference of 180° in an electrical angle from the other excitation winding.